They say drivers between the ages of 25 and 29 could save an average of £443 by switching 21 days before their renewal.
Meanwhile, drivers aged between 30 and 39 were likely to save £367 renewing 21 days early with those between 40 and 49 saving £289 on cover.
Confused.com also confirmed premiums are usually at their cheapest between 21 and 30 days before a policy expires.
He said drivers who leave it to the last minute will be considered “a more risky person” which could make someone more likely to claim on an agreement.
He said: “This is not about your renewal price, it’s the cheapest price you’ll get on a comparison on the days before you renew.
“If you try and get a quote 30 days before the price is pretty high then it drops very rapidly.
“Then it starts to go up and up and up until we are talking about renewing at the last moment which is nearly twice the cost.
“You’re saying ‘that makes no sense’, well, there is a reason.
“Insurance pricing is based on risk and if you are the type of person who leaves it to the last minute their risk charts show you’re a more risky person so they will charge you more.
“So play their risk odds against them and renew earlier in that sweet spot of three to four weeks and you can save money.”